Date of Award
Bachelor of Science
Paper Science and Engineering
The purpose of this project was to evaluate several operating variables of the newly installed Western Michigan University Jones DD 3000 refiner. The operating variables were refiner load in amperes, throughput rate in gallons per minute, and disk speed in revolutions per minute.
On the fiber level, Canadian Standard Freeness was most dependent upon the load and somewhat less dependent upon the tonnage rate and speed. The tonnages used were 4.8, 9.6, and 14.4 T/D. At 9.6 T/D, the refiner used the least HPD/T per 100 ml C.S.F. drop throughout the 300-500 ml C.S.F. range. At 4.8 and 9.6 T/D, the HPD/T increased per 100 ml C.S.F. drop over the same freeness range.
Lower refiner speeds produced similar C.S.F. results at higher tonnage rates at the same intensity, where less disk speed required a substantial increase in the power used over the higher tonnage rate.
Maximum sheet quality was developed in the mullen, tensile, and fold tests at high loads and low C.S.F. The tear test remained almost constant under varied loads. Sheet strength was highest at low and medium throughput rates, where the medium throughput developed nearly the same strength as the low throughput with a large savings in HPD/T.
In the optical tests, brightness dropped while opacity increased at greater values of HPD/T. The opacity results were opposite to the normally expected drop at higher HPD/T.
Further evaluation of the Western Michigan University DD 3000 suggested with respect to Mono-Flo and Duo-Flo, consistency changes, pulp mixtures, disk configurations, and speed changes.
Flohr, Gary, "The Effects of Variable Double Disk Refining Action on Sheet and Fiber Properties" (1976). Paper Engineering Senior Theses. 137.